Posted on by Jason Major

Cassini’s View of Another Pale Blue Dot

Uranus as seen by Cassini on July 19, 2013 (NASA/JPL-Caltech/SSI)

When you hear the words “pale blue dot” you’re probably reminded of the famous quote by Carl Sagan inspired by an image of Earth as a soberingly tiny speck, as imaged by Voyager 1 on Feb. 14, 1990 from beyond the orbit of Pluto. But there’s another pale blue world in our Solar System: the ice giant Uranus, and its picture was captured much more recently by the Cassini spacecraft from orbit around Saturn on April 11, 2014.

Released today by the Cassini Imaging Team, the image above shows Uranus as a tiny blue orb shining far beyond the bright hazy bands of Saturn’s F ring.

“Do you relish the notion of being a Saturnian, and gazing out from the lofty heights of Saturn at the same planets we see here from the Earth?”
– Carolyn Porco, Cassini Imaging Team Leader

Uranus’ coloration is a result of methane high in its frigid atmosphere. According to the description on the CICLOPS site, “methane on Uranus — and its sapphire-colored sibling, Neptune — absorbs red wavelengths of incoming sunlight, but allows blue wavelengths to escape back into space, resulting in the predominantly bluish color seen here.”

This was also the first time Uranus had been imaged by the Cassini spacecraft, which has been in orbit around Saturn since 2004. In fact its ten-year orbital anniversary will come on July 1.

This image adds one more planet to the list of worlds captured on Camera by Cassini, which made headlines last fall when a glorious mosaic was released that featured a backlit Saturn in eclipse surrounded by its luminous rings, the specks of several of its moons, and the distant dots of Venus, Mars, and the Earth and Moon. Made from 141 separate exposures, the mosaic was captured on July 19, 2013 — known by many space aficionados as “the day the Earth smiled” as it was the first time the world’s population was alerted beforehand that its picture would be taken from over 900 million miles away.

Saturn — with its terrestrial spacecraft in tow — was about 28.6 AU away from Uranus when the image was acquired. That’s about  4.28 billion kilometers (2.66 billion miles). From that distance the glow of the 51,118-kilometer (31,763-mile) -wide Uranus is reduced to a mere few pixels (which required digital brightening by about 4.5x, as well.)

Read more on the Cassini Imaging Central Laboratory for Operations (CICLOPS) page here and in a news release from NASA’s JPL here.

Image credit: NASA/JPL-Caltech/SSI. Source: Carolyn Porco, CICLOPS Director

Posted on by Nancy Atkinson

Astrophoto: Uranus at Opposition

Uranus, imaged from Italy on October 3, 2013, when the planet was at opposition. Credit and copyright: Giuseppe Petricca.

Last week, we asked if you were looking for an observing challenge: looking for planet Uranus when it reached opposition — where it is opposite the Sun the sky, meaning the planet rises as the Sun sets. Giuseppe Petricca from Italy took the challenge and ran with it. His skies over Sulmona, Abruzzo in Italy cleared, and not even 12 hours after the official time of opposition he got this shot using his new Toucam Pro II on a Newtonian 200/1000 on EQ5 unmotorized mount.

Nice!

Want to get your astrophoto featured on Universe Today? Join our Flickr group or send us your images by email (this means you’re giving us permission to post them). Please explain what’s in the picture, when you took it, the equipment you used, etc.

Posted on by David Dickinson

Uranus: A Guide to its 2013 Opposition

Credit:

Up for a challenge? Got a big 12” light bucket of a Dobsonian telescope and looking for something new to point it at? This week, as the Moon reaches New phase on October 4th and stays safely out of the late evening sky, why not check out Uranus and its retinue of moons. And yes, we’ve heard just about ALL the Uranus jokes —its pronounced yer-in-us, thank you very much — but feel free to attempt to pen an original if you must.

Now, back to astronomy. Uranus reaches opposition for 2013  on Thursday, October 3rd at 14:00 Universal Time. Opposition is the point in time that an outer planet rises as the Sun sets. In the case of Uranus, its opposition dates advance forward by about 4-5 days each year.

Credit
The current location of Uranus in Pisces. Created by the author using Stellarium. (click to enlarge).

This also marks the start of the best time to hunt for the planet among the star fields of the constellation Pisces. Uranus will reach its maximum elevation above the southern horizon for northern hemisphere viewers for early October around local midnight. For observers south of the equator, Uranus will transit to the north. Incidentally, Uranus also currently sits near the equinoctial point occupied by the Sun during the March equinox, making viewing opportunities nearly equal for both hemispheres.

Uranus is 19.04 astronomical units distant during opposition 2013, or about 158 light minutes away. Shining at magnitude +5.8, Uranus presents a tiny blue-green disk just under 4” across at opposition.

Uranus currently lies six degrees SW of the +4.4 magnitude star Delta Piscium, on the border of the constellations Pisces and Cetus. Uranus will actually be crossing once again into the non-zodiacal constellation of Cetus later this year.

Discovered in 1781 by Sir William Herschel, Uranus has only completed 2 full orbits (2.75 to be precise) in its 84.3 year trips about the Sun. We can be thankful that William’s proposal to name the planet Geogium Sidus after his benefactor King George the III didn’t stick!

Starry Night Education
The path of Uranus into Cetus. Created by the author using Starry Night Education software.

At opposition, Uranus will be located at;

Right Ascension: 0h 40’

Declination: +3° 25’

Five of the 27 known moons of Uranus are also within the grasp of a moderate-sized backyard scope as well. The trick is to catch ‘em near greatest elongation, when they appear farthest from the “glare of Uranus” (hey, there’s a freebie for a snicker or two). An eyepiece equipped with an occulting bar, or simply nudging Uranus out of the field of view can also help.

With magnitudes ranging from +13 to +16, the moons of Uranus are similar in brightness to Neptune’s large moon Triton or the tiny world Pluto.

The five brightest moons of Uranus and their respective maximum elongations are:

Chart constructed by author.

And here’s a handy finder chart for the coming month, showing maximum elongations for each:

A corkscrew graph featuring the greatest elongations for the five brightest moons of Uranus. (Created by Ed Kotapish using PDS Rings Node).
A corkscrew graph featuring the greatest elongations for the five brightest moons of Uranus through October. (Created by Ed Kotapish using PDS Rings Node).

The first two moons were named Titania and Oberon by William’s son John after characters from William Shakespeare’s A Mid-Summer Night’s Dream. William discovered the first two moons of Uranus on the night of January 11th, 1787 using his 49.5” reflector. His scopes were so advanced for his day, that it wasn’t until over a half a century later that William Lassell discovered Umbriel and Ariel using the Liverpool Observatory’s 24” reflector in 1851.

Gerard Kuiper would later add tiny Miranda to the list, nabbing it with the McDonald Observatory’s 82” Otto Struve Telescope in 1948. We would then have to wait until Voyager 2’s 1986 flyby of Uranus in 1986 to add more. To date, Voyager 2 remains the only spacecraft to visit Uranus and Neptune.

The current convention established by the International Astronomical Union is to name the moons of Uranus after characters from the plays of Shakespeare or Alexander Pope’s Rape of the Lock.

There’s still a wide range of names in said literature to choose from!

It’s interesting to note that the orbits of the moons of Uranus are also currently tipped open about 25 degrees to our line of sight and widening. They were edge on in December 2007, and will be perpendicular to our Earthly view come 2029, after which they’ll head back to edge on in 2049. This is because Uranus and the orbits of its moons are tipped at a 97 degree angle relative to the planet’s orbit. This is why elongations for its moons are often quoted it terms of “north and south” of the planet, rather than the familiar east and west. Shadow transits of the moons can occur with about a year and a half during plane-crossing seasons, but they’re ~42 years apart and tough to spot on the tiny disk of Uranus!

October 4th Starry Night Education
An example of the orientation of Uranus’s moons on October 4th, with Oberon at greatest elongation. Note that Miranda is the tiny unlabeled moon with the interior orbit. (Created by the author using Starry Night Education software).

Uranus also reached aphelion in 2009 at 20.099 AU from the Sun —we’re still at the farther end of the spectrum, as oppositions of Uranus can range from 19.09 to 17.28 AU distant.

Uranus will rise earlier on each successive evening until it reaches quadrature at the end of the year on December 30th. At this point, it’ll be roughly due south at local sunset. Keep in mind, there’s also another ice giant worth hunting for in the adjacent constellation of Aquarius named Neptune.

So ignore those bad puns, and be sure to take out that 10” (scope, that is) and point it at Uranus!

Posted on by Tammy Plotner

Trojan Asteroid Found Orbiting Uranus

One of three discovery images of 2011 QF99 taken from CFHT on 2011 October 24 (2011 QF99 is inside the green circle). This is the first of three images of the same patch of sky, taken one hour apart, that were then compared to find moving light-sources.

What’s new in the outer reaches of our solar system? Try the discovery of a Trojan asteroid orbiting Uranus. While a plethora of puns exist for this simple fact, the reality check is that this means there are far more of these objects out there than astronomers expected. The new Trojan even has a name – 2011 QF99!

A Trojan asteroid is a transient space rock which is temporarily captured by the gravity of a giant planet. It shares the planet’s orbital path, locked into a specific position known as a Lagrange point. What makes 2011 QF99 unusual is its presence in the outer solar system. Researchers found the scenario a bit unlikely. Why? The answer is simply because of planet size. According to theory, the strong gravitational pull of the larger neighboring planets should have destabilized any captured asteroid’s orbit and shot Uranian Trojans out of the neighborhood long ago.

So just how did this 60 kilometer-wide conglomeration of ice and rock end up circling Uranus? Astronomers turned towards computer modeling for the answer. The research team, including UBC astronomers Brett Gladman, Sarah Greenstreet and colleagues at the National Research Council of Canada and Observatoire de Besancon in France, did a simulation of the solar system and its co-orbital objects – including Trojan asteroids. A short-term animation showing the motion of 2011 QF99, as seen from above the north pole of the solar system can be found here.

“Surprisingly, our model predicts that at any given time three percent of scattered objects between Jupiter and Neptune should be co-orbitals of Uranus or Neptune,” says Mike Alexandersen, lead author of the study to be published tomorrow in the journal Science.

Until now, no one had made any estimates on the percentage of possible outer solar system Trojans. Unexpectedly, the amount ended up being far greater than earlier estimates. Just over the last 10 years, several temporary Trojans and co-orbitals have been cataloged and 2011 QF99 is one of them. It made its home around Uranus within the last few hundred thousand years and will eventually – in about a million years – escape Uranus’ gravity.

“This tells us something about the current evolution of the solar system,” says Alexandersen. “By studying the process by which Trojans become temporarily captured, one can better understand how objects migrate into the planetary region of the solar system.”

Original Story Source: UBC News Release.

Posted on by Elizabeth Howell

Uranus Is Being Chased By Asteroids!

A Sharper View Of Uranus
Uranus viewed in the infrared spectrum, revealing internal heating and its ring system. Image Credit: Lawrence Sromovsky, (Univ. Wisconsin-Madison), Keck Observatory

As Uranus speeds in its orbit in the solar system, there are three large space rocks that are in lockstep with the gas giant, according to new simulations. Two of them are wobbling in unstable “horseshoe” orbits near Uranus, while the third is in a more reliable Trojan orbit that is always 60 degrees in front of the planet.

The largest of this small group is the asteroid Crantor, which is 44 miles (70 kilometers) wide. Its horseshoe orbit, and that of companion 2010 EU65, means the space rocks seesaw between being close to Uranus and further away. They should stay in that configuration for a few million years.

The last of the group is 2011 QF99, in a Trojan orbit near one of Uranus’ Lagrangian points — sort of like a celestial parking spot where an object can hang out without undue influence from the balanced gravitational forces.

An artists impression of an asteroid belt(credit: NASA)
An artists impression of an asteroid belt(credit: NASA)

The results illustrate the importance of space rocks that are outside of the main asteroid belt between Mars and Jupiter.

There are several kinds of these asteroids (classified by their orbits) that follow around planets in the solar system. Earth itself, for example, has at least one Trojan asteroid.

“Crantor currently moves inside Uranus’ co-orbital region on a complex horseshoe orbit. The motion of this object
is primarily driven by the influence of the Sun and Uranus, although Saturn plays a significant role in destabilizing its orbit,” the authors wrote in their new study.

“Although this object follows a temporary horseshoe orbit, more stable trajectories are possible and we present 2010 EU65 as a long-term horseshoe librator candidate in urgent need of follow-up observations.”

The results are described in Crantor, a short-lived horseshoe companion to Uranus  (Astronomy & Astrophysics, March 3, 2013.)

Source: Servicio de informacíon y noticias cientifícas

Posted on by Jason Major

27 Years Ago: Voyager 2’s Visit to Uranus

Image of Uranus’ crescent taken by a departing Voyager 2 on January 25, 1986 (NASA/JPL)

27 years ago today, January 24, 1986, NASA’s Voyager 2 spacecraft sped past Uranus, becoming simultaneously the first and last spacecraft to visit the blue-tinged gas giant, third largest planet in the Solar System.

The image above shows the crescent-lit Uranus as seen by Voyager 2 from a distance of about 965,000 km (600,000 miles.) At the time the spacecraft had already passed Uranus and was looking back at the planet on its way outwards toward Neptune.

Although composed primarily of hydrogen and helium, trace amounts of methane in Uranus’ uppermost atmosphere absorb most of the red wavelengths of light, making the planet appear a pale blue color.

12bg-1

Image of the 1,500-km-wide Oberon acquired by Voyager 2 on Jan. 24, 1986 (NASA/JPL)

The second of NASA’s twin space explorers (although it launched first) Voyager 2 came within 81,800 kilometers (50,600 miles) of Uranus on January 24, 1986, gathering images of the sideways planet, its rings and several of its moons. Voyager 2 also discovered the presence of a magnetic field around Uranus, as well as 10 new small moons.

6bg

Three moons discovered by Voyager 2 in 1986 (NASA/JPL)

Data gathered by Voyager 2 revealed that Uranus’ rate of rotation is 17 hours, 14 minutes.

At the time of this writing, Voyager 2 is 15,184,370,900 km from Earth and steadily moving toward the edge of the Solar System at a speed of about 3.3 AU per year. At that distance, signals from Voyager take just over 14 hours and 4 minutes to reach us.

See images from Voyager 2’s visit of Uranus here, and check out a video of the August 20, 1977 launch below along with more images from the historic Voyager mission’s “Grand Tour” of the outer Solar System.

Posted on by Nancy Atkinson

Uranus has Bizarre Weather

New infrared images of Uranus show details not seen before. Credit: NASA/ESA/L. A. Sromovsky/P. M. Fry/H. B. Hammel/I. de Pater/K. A. Rages

Here’s the scene: a thick, tempestuous atmosphere with winds blowing at a clip of 900 km/h (560 mph); massive storms that would engulf continents here on Earth, and temperatures in the -220 C (-360 degree F) range. Sounds like a cold Hell, but this is the picture emerging of the planet Uranus, revealed in new high-resolution infrared images from the Keck Observatory in Hawaii, exposing in incredible detail the bizarre weather of a planet that was once thought to be rather placid.

“My first reaction to these images was ‘wow’ and then my second reaction was ‘WOW,'” said Heidi Hammel, a co-investigator on the new observations. “These images reveal an astonishing amount of complexity in Uranus’ atmosphere. We knew the planet was active, but until now much of the activity was masked by noise in our data.”

Voyager 2’s view of Uranus. Credit: NASA

With its beautiful blue atmosphere, Uranus can seem rather tranquil at first glance. Even the flyby of Voyager 2 in 1986 revealed a rather “bland” blue ball. But coming into focus now with the new are large weather systems, and even though they are probably much less violent than storms on Earth, the weather on Uranus is just…bizarre.

“Some of these weather systems,” said Larry Sromovsky, from the University of Wisconsin-Madison who led the new study using the Keck II telescope, “stay at fixed latitudes and undergo large variations in activity. Others are seen to drift toward the planet’s equator while undergoing great changes in size and shape. Better measures of the wind fields that surround these massive weather systems are the key to unraveling their mysteries.”

Sromovsky, Hammel and their colleagues are using new infrared techniques to deliver some of the “most richly detailed views of Uranus yet obtained by any instrument on any observatory. No other telescope could come close to producing this result,” Sromovsky said.

What they are seeing are previously undetected, small but widely distributed weather feature, and they hope the movements of these features can help make sense of the planet’s odd pattern of winds.

They observed a scalloped band of clouds just south of Uranus’ equator and a swarm of small convective features in the north polar regions of the planet. Features like this don’t seem to be in the southern polar regions, but are similar to the types of “popcorn” –type clouds seen on Saturn. Uranus’ north pole is not visible from Earth night now, but when it does come into view, the researchers wouldn’t be surprised to see a polar vortex feature similar to what has been seen at Saturn’s south pole.

The driver of these features must be solar energy because there is no other detectable internal energy source.

“But the Sun is 900 times weaker there than on Earth because it is 30 times further from the Sun, so you don’t have the same intensity of solar energy driving the system,” said Sromovsky. “Thus the atmosphere of Uranus must operate as a very efficient machine with very little dissipation. Yet the weather variations we see seem to defy that requirement.”

One possible explanation, is that methane is pushed north by an atmospheric conveyor belt toward the pole where it wells up to form the convective features visible in the new images. The phenomena may be seasonal, the team said, but they are still working on trying to put together a clear seasonal trend in the winds of Uranus.

“Uranus is changing,” he said, “and there is certainly something different going on in the two polar regions.”

The images were released at the American Astronomical Society’s Division for Planetary Sciences meeting taking place this week.

Source: University of Wisconsin-Madison

Posted on by Nancy Atkinson

The Moon from Earth As You’ve Never Seen it Before

The Morteus region on the Moon, taken from the suburbs of Paris, France. Credit: Thierry Legault. Used by permission.

Think this is an orbital view of the Moon? Guess again. Astrophotographer Thierry Legault took this image from his backyard in the suburbs of Paris, France! He’s taken a series of images of the Moon the past few nights that will blow your mind when you consider they were taken from Earth, within the confines of the metropolis of Paris (largest city in France, 5th largest in the EU, 20th largest in the world). Thierry used a Celestron C14 EdgeHD (356mm) and Skynyx2.2 camera. You definitely want to click on these images for the larger versions on Thierry’s website, and he suggests using a full-HD screen in subdued surroundings.

Additionally, Thierry also recently took images of Mercury and Uranus that include incredible detail.

Plato, Mons Pico and Montes Teneriffe as seen on Sept 8th, 2010, from the suburbs of Paris, France. Credit: Thierry Legault. Used by permission.

The clarity and detail are just tremendous. See all of Thierry’s recent lunar images at this link. He has a collection of twelve different images of various regions on the Moon and all are stunning.

Below are his images of Mercury and Uranus. In the image of Mercury, surface details are visible, and the cloud belts are even visible on the images of Uranus:

Incredibly detailed view of Mercury on August 23, 2012, as seen from Blancourt, France. Credit: Thierry Legault. Used by permission.

Uranus, as seen on September 9, 2012 from Blancourt, France. Credit: Thierry Legault. Used by permission.

Thanks, as always, to Thierry Legault for sharing his images and allowing us to post them. Check out his website: http://legault.perso.sfr.fr/ for more wonderful images and information about how he does his amazing astrophotography.

Posted on by Jason Major

Hubble Reveals Curious Auroras on Uranus

Bright spots of Uranus' short-lived auroras have been imaged with the Hubble Space Telescope.

[/caption]

Astronomers have finally succeeded in capturing the first Earth-based images of the curious and fleeting auroras of Uranus using the Hubble Space Telescope, careful planning… and no small amount of luck.

Unlike Earthly auroras, whose long-lived curtains of glowing green, red and purple have been the subject of countless stunning photos over the past months, Uranus’ auroras are relatively dim and short-lived, lasting only several minutes at most. They were first witnessed on Uranus by Voyager 2 in 1986, but never by any Earth-based telescopes until November of 2011. Using Hubble, an international team of astronomers led by Laurent Lamy from the Observatoire de Paris in Meudon, France spotted two instances of auroras on the distant planet… once on November 16 and again on the 29th.

Two instances of Uranian aurora imaged in Nov. 2011. (L. Lamy)

Auroras are known to be created by a planet’s magnetosphere, which on Earth is aligned closely with the rotational axis — which is why auroras are seen nearest the polar latitudes. But Uranus’ magnetic field is quite offset from its rotational axis, which in turn is tipped nearly 98 degrees relative to its orbital path. In other words, Uranus travels around the Sun rolling on its side! And with a 60-degree difference between its magnetic and rotational axis, nothing on Uranus seems to point quite where it should. This — along with its 2.5-billion-mile (4 billion km) distance — makes for a “very poorly known” magnetic field.

“This planet was only investigated in detail once, during the Voyager flyby, dating from 1986. Since then, we’ve had no opportunities to get new observations of this very unusual magnetosphere,” said Laurent Lamy, lead author of the team’s paper Earth-based detection of Uranus’ aurorae.

Rather than rings of bright emissions, as witnessed on Earth as well as Saturn and Jupiter, the Uranian auroras appeared as bright spots of activity on the planet’s daytime side — most likely a result of Uranus’ peculiar orientation, as well as its seasonal alignment.

It’s not yet known what may be happening on Uranus’ night side, which is out of view of Hubble.

When Voyager 2 passed by Uranus in 1986 the planet was tipped such that its rotational axis was aimed toward the Sun. This meant that its magnetic axis —  offset by 60 degrees — was angled enough to encounter the solar wind in much the same way that Earth’s does. This created nightside auroras similar to Earth’s that Voyager saw.

By 2011, however, Uranus — which has an 84-year-long orbit — was near equinox and as a result its magnetic axis was nearly perpendicular with its orbital plane, aiming each end directly into the solar wind once a day. This makes for very different kinds of auroras than what was seen by Voyager; in fact, there’s really nothing else like it that astronomers know of.

“This configuration is unique in the solar system,” said Lamy.

Further investigations of Uranus’ auroras and magnetic field can offer insight into the dynamics of Earth’s own magnetosphere and how it interacts with the solar wind, which in turn affects our increasingly technological society.

The team’s paper will be published Saturday in Geophysical Research Letters, a journal of the American Geophysical Union.

Read the release from the AGU here.

Posted on by Tammy Plotner

Weekly SkyWatcher’s Forecast – March 12-18, 2012

Venus & Jupiter above Backyard Observatory - Credit: John Chumack

[/caption]

Greetings, fellow SkyWatchers! What an awesome display of planets! Please take the time to walk outdoors just after skydark – regardless of where you live – and enjoy the bright display of Venus and Jupiter! However, this isn’t the only planetary action going on this week… Mars and M96 pair up, as well as Uranus and the Moon. There’s even a Southern Hemisphere meteor shower to enjoy! Pretty exciting, huh? Join the party by getting out your binoculars or telescopes and meet me for more in the backyard…

Monday, March 12 – No. That’s not the “headlights” of a UFO on the western horizon tonight… It’s a very cool pairing of Venus and Jupiter! It’s not often you see the two visually brightest planets making a close visual pass at each other and tonight you’ll spot the inner planet to the south and the outer planet to the north. This would make a great photo opportunity! Why not consider adding something interesting to your picture like a scenic building, tree, or even a person? Watch in the days ahead as Jupiter appears to stay in the same spot at the same time, yet Venus will climb higher.

Tonight let’s return again to NGC 2362 and start at the cluster’s north-northeast corner to have a look at a single, unusual star – UW Canis Majoris. At magnitude 4.9, this super-giant spectroscopic binary is one of the most massive and luminous in our galaxy. Its two stars are separated by only 27 million kilometers (17 million miles) and revolve around each other at a frenzied pace – in less than four and a half days. This speed means the stars themselves are flattened and would appear to be almost egg-shaped. The primary itself is shedding material that’s being collected by the secondary star.

Now drop southwest of NGC 2362 for another open cluster – NGC 2354 (Right Ascension: 7 : 14.3 – Declination: -25 : 44). While at best this will appear as a small, hazy patch to binoculars, NGC 2354 is actually a rich galactic cluster containing around 60 metal-poor members. As aperture and magnification increase, the cluster shows two delightful circle-like structures of stars, similar to a figure 8. Be sure to make a note… You’ve captured another Herschel 400 object!

Tuesday, March 13 – On this day in 1781, Uranus was discovered by William Herschel. Also on this day, in 1855, Percival Lowell was born in Boston. Educated at Harvard, Lowell went on to found the observatory which bears his name in Flagstaff, Arizona, and spent a lifetime studying Mars. During the early morning hours, you can honor Lowell by seeing Mars yourself – it’s best viewed when as high a possible on the ecliptic. While there won’t be a great many details, think of how many strides have been made since Lowell’s time and how advanced our knowledge of Mars has become!

Tonight let’s hop about four fingerwidths east-northeast of Sirius. Look for 5th magnitude SAO 152641 to guide you to a faint patch of stars in binoculars and a superb cluster in a telescope – NGC 2360 (Right Ascension: 7 : 17.8 – Declination: -15 : 37). Comprised of around eighty 10th magnitude and fainter stars, this particular cluster will look like a handful of diamond dust scattered on the sky. Discovered by Caroline Herschel in 1783, this intermediate-aged galactic cluster is home to red giants and heavy in metal abundance. Mark your notes, because not only is this a Herschel object, but is known as Caldwell 58 as well!

Wednesday, March 14 – Today is the birthday of Albert Einstein. Born in 1879, Einstein was one of the finest minds of our times. He developed the theory of gravity in terms of spacetime curvature – dependent on the energy density. Winner of the 1921 Physics Nobel prize, Einstein’s work on the photoelectric effect is the basis of modern light detectors.

Tonight let’s hop about a fistwidth north of bright Eta Canis Majoris and have a look at a “double cluster” – NGC 2383 (Right Ascension: 7 : 24.8 – Declination: -20 : 56) and NGC 2384 (Right Ascension: 7 : 25.1 – Declination: -21 : 02). Just showing in binoculars as a faint patch, this pair will begin resolution with larger scopes. Studied photometrically, it would appear these fairly young clusters have contaminated each other by sharing stars – which has also occurred in some clusters located in the Magellanic Clouds. Enjoy this unusual collection of stars…

Thursday, March 15 – Today celebrates the birth of Nicolas Lacaille. Born in 1713, Lacaille’s measurements confirmed the Earth’s equatorial bulge. He also named fourteen southern constellations. To honor Lacaille tonight, let’s begin some explorations in a constellation he named – Puppis!

For SkyWatchers living in high northern latitudes, you’ll never see all of this constellation, but there will be some things for you to explore, as well as a great deal for our friends in the southern hemisphere. The first is a Herschel object that lies directly on the galactic equator around five degrees north-northwest of Xi.

NGC 2421 (Right Ascension: 7 :36.3 – Declination: -20 : 37) is a magnitude 8.3 open cluster that will look like an exquisitely tiny “Brocchi’s Cluster” in binoculars and begin good resolution of its 50 or so members to an intermediate telescope, in an arrowhead-shaped pattern. It’s bright, it’s fairly easy to find, and it’s a great open cluster to add to your challenge study lists!

If you’re looking for a curiosity, then look no further than Leo and Mars. Tonight the happy red planet is situated just to the east of Messier 96 (Right Ascension: 10 : 46.8 – Declination: +11 : 49)! Enjoy celestial mechanics over the next few nights as Mars gently changes its position in relation with this distant galaxy… and gets much closer!

Friday, March 16 – On this day in 1926, Robert Goddard launched the first liquid-fuel rocket. But he was first noticed in 1907 when a cloud of smoke issued from a powder rocket fired in the basement of the physics building in Worcester Polytechnic Institute. Needless to say, the school took an interest in the work of this shy student. Thankfully they did not expel him, and thus began his lifetime of work in rocket science. Goddard was also the first to realize the full implications of rocketry for missiles and space flight, and his lifetime of work was dedicated to bringing this vision to realization. While most of what he did went unrecognized for many years, tonight we celebrate the name of Robert H. Goddard. This first flight may have gone only 12 meters, but forty years later on the date of his birth, Gemini 8 was launched, carrying Neil Armstrong and David Scott into orbit!

Let’s begin our observing evening with Mars. While you may have been keeping track of its position, did you know that it’s less than a degree away from a Messier object tonight? That’s right! You’ll find the dusty red planet just to the north of M96 (Right Ascension: 10 : 46.8 – Declination: +11 : 49).

Tonight we’ll pick up a challenge cluster and a planetary nebula on the Herschel list by returning to NGC 2421 and hopping about a fingerwidth northeast for NGC 2432 (Right Ascension: 7 : 40.9 – Declination: -19 : 05). This small, loose open cluster is rather dim and contains around 20 or so faint members shaped like the letter B. About another degree northeast is NGC 2440 – an elongated, small 11th magnitude planetary nebula. Look for its central star to cause a brightening and up the magnifying power to reveal it.

While out, be on watch for the Corona-Australids meteor shower. While the fall rate is low – 5 to 7 per hour – our friends in the southern hemisphere might stand a chance with this one!

Saturday, March 17 – On this day in 1958, the first solar-powered spacecraft was launched. Named Vanguard 1, it was an engineering test satellite. From its orbital position, the data taken from its transmission helped to redefine the true shape of the Earth.

Tonight let’s return to Xi Puppis and head less than a fingerwidth east-northeast for Herschel study NGC 2482 (Right Ascension: 7 : 54.9 – Declination: -24 : 18). At magnitude 7, this small fuzzy spot in binoculars will resolve into around two dozen stars to the telescope. Look for the diagonal chain of stars along its edge.

Now let’s have a look at an open cluster easily located in northeastern Orion. This 5.9 magnitude scattered group of stars may have been first observed by Giovanni Batista Hodierna in the mid-17th century. While bright enough to have been a Messier object, William Herschel added it to his log of discoveries on October 15, 1784, as H VIII.24. Of the 30 known stars associated with this 3,600 light-year distant group, the brightest is 50 million years old. A half-dozen of the cluster’s very brightest members can be seen in small scopes at mid-range powers. Look for NGC 2169 (Right Ascension: 6 : 08.4 – Declination: +13 : 57) slightly less than a fist width north-northeast of Betelguese and slightly south of Xi and Nu Orionis.

Sunday, March 18 – Although you can’t see it with just your eyes, Uranus is less than a degree from the Moon this morning. For some areas this could be an occultation, so be sure to check IOTA information!

Today in 1965, the first ever spacewalk was performed by Alexei Leonov onboard the Soviet Voskhod spacecraft. The “walk” only lasted around 20 minutes and Alexei had problems in re-entering the spacecraft because his space suit had enlarged slightly. Imagine his fear as he had to let air leak out of his space suit in order to squeeze back inside. When they landed off target in the heavily forested Ural Mountains, the crew of two had to spend the night in the woods surrounded by wolves. It took over twenty-four hours before they were located and workers had to chop their way through the forest and recover them on skis. Brave men!

Tonight let’s honor them by studying a small area which contains not only three Herschel objects – but two Messiers as well – M46 and M47. You’ll find them less than a handspan east of Sirius and about a fistwidth north of Xi Puppis.

The brighter of the two clusters is M47 (Right Ascension: 7 : 36.6 – Declination: -14 : 30) and at 1600 light-years away, it’s a glorious object for binoculars. It is filled with mixed magnitude stars that resolve fully to aperture with the double Struve 1211 near its center. While M47 is in itself a Herschel object, look just slightly north (about a field of view) to pick up another cluster which borders it. At magnitude 6.7, NGC 2423 isn’t as grand, but it contains more than two dozen fairly compressed faint stars with a lovely golden binary at its center.

Now return to M47 and hop east to locate M46 (Right Ascension: 7 : 41.8 – Declination: -14 : 49). While this star cluster will appear to be fainter and more compressed in binoculars, you’ll notice one star seems brighter than the rest. Using a telescope, you’ll soon discover the reason. 300 million year old M47 contains a Herschel planetary nebula known as NGC 2438 in its northern portion. The cluster contains around 150 resolvable stars and may involve as many as 500. The bright planetary nebula was first noted by Sir William Herschel and then again by John. While it would appear to be a member of the cluster, the planetary nebula is just a little closer to us than the cluster. Be sure to mark your notes… There’s a lot there in just a little area!

Until next week? May all of your journeys be at light speed!

Many thanks to John Chumack for the inspiring image!